| 摘要 |
PURPOSE:To readily prevent occurrence of flare or ghost without requiring coating of an antireflection coating, by forming the outer peripheral surface of a glass lens so as to provide respective different specific surface roughnesses in the optical axis and radial directions. CONSTITUTION:This glass lens (12a) is formed so as to provide an outer peripheral surface having 0-2mum surface roughness in the optical axis direction and 2-20mum surface roughness in the radial direction. The above-mentioned glass lens (12a) is produced by using a multipart drum mold 13 formed so as to provide 0-2mum surface roughness in the optical axis direction and 2-20mum surface roughness in the radial direction on the inner surface from a material having a thermal expansion coefficient same as or smaller than that of a glass material 12 to be formed, holding the glass material 12 by this multipart drum mold 13, heating the glass material 12 in a heating furnace 8, conveying the drum mold 13 to a space between a pair of forming molds 3 and 4 by a conveying member 17 and press forming the glass material 12 with the forming molds 3 and 4. |
